AJE | BEN MUDRAK, PHD VERB TENSE IN SCIENTIFIC MANUSCRIPTS Choosing the correct verb tense for each section of a below. In general terms, the tense of a verb reflects scientific manuscript can be challenging, but it is worth the timing of the action: the past tense indicates the effort. Editorials in several journals have noted that an action already occurred, the present tense that proper verb tense is an important aspect of a well indicates that the action is currently occurring, and written manuscript1,2,3 and some journals and publishers the future tense indicates that the event has not yet specifically mention verb tense in their style guides.4,5 occurred. Verbs can also be conjugated into a past, Here, we suggest the appropriate verb tenses to use when present, or future perfect tense, in which the action writing your next manuscript. is defined relative to another point in time (see the examples below). First, some background about the verb tenses discussed TITLE. accompanies. First, when stating a fact that is widely For many journals, the manuscript title does not need accepted, the present tense is appropriate. Examples to be a complete sentence, and no verb is necessary. of such a statement include “DNA is composed of In cases where a complete sentence is appropriate, use four nucleotides” or “trypanosomes exhibit global the simple present tense to describe a conclusion that trans-splicing of RNA transcripts.” Use of the present the manuscript supports (e.g., “Gene X is required for tense signifies that the statement reflects the current intestinal cell differentiation” or “Frameshift mutations understanding of the matter at hand. in gene X cause abnormal notochord development in Most introductions also include references to previous zebrafish”). research. When referring to a previous study with INTRODUCTION. results that are still relevant, use the present perfect The introduction often includes several verb tenses, each tense (a form of the verb ‘have’ plus a past participle, providing a different context for the statement that is such as “have shown” or “has been shown”). This tense 1 Carraway LN “Improve scientific writing and avoid perishing.” Am Midl Nat 155(2):383-394 (2006) 2 Lin P-Y and Y-R Kuo “A guide to write a scientific paper for new writers.” Microsurgery 32(1):80-85 (2012) 3 Fahy K “Writing for publication: argument and evidence.” Women Birth 21(3):113-117 (2008) 4 Eukaryotic Cell Instructions to Authors http://ec.asm.org/site/misc/journal-ita_abb.xhtml#01 5 “Writing a scientific paper” in The ACS Style Guide: A Manual for Authors and Editors ed. JS Dodd (Washington, DC: American Chemical Society, 1997) AJE is the leading provider of manuscript services to academics and researchers worldwide. AJE.com demonstrates that the action occurred in the past but still applies in the present. Phrases like “Johnson et al. METHODS have shown that gene X is part of an operon” or “unusual glycosylation events have been observed in these cells” The methods section should use are appropriate because the research or observation the past tense because it is a was made in the past, but the results are still valid. This tense is also used when the event began in the past but report of what was done during continues in the present (“patients with XYZ syndrome the course of the study. have been surveyed for the past ten years”). Please note that the present tense is used when a specific result, figure, or paper is the subject of a sentence. Like a For example, the methods should be written in the form movie or book, published research is still available for of descriptions such as “we tested independently derived readers to examine, and a paper therefore continues to cultures for resistance to trimethoprim” or “cells were express its conclusions. Examples of statements about transfected, irradiated, and assayed for DNA damage.” previous research using the present tense include “the When one action occurred before another, the past results of their study indicate that the drug is highly perfect tense can be used to indicate the earlier action, effective” or “a landmark paper from Smith’s lab describes with the subsequent action in the simple past tense. the discovery of this new organelle.” The past perfect tense is formed by combining the word In some other parts of an introduction, the past tense ‘had’ with the past participle (typically the ‘-ed’ or ‘-en’ is needed. When referring specifically to the methods form) of a verb. Examples combining the past and past used in a previous paper, the past tense is best. For perfect tenses include “the cells that had been irradiated example, it is correct to say “Smith and Anderson sampled [past perfect] were assayed [past] for DNA damage” 96 swamps and found 156 distinct dragonfly species” or and “patients who had elected [past perfect] to undergo “gene X was first cloned into a shuttle vector in 2003.” surgery completed [past] questionnaires.” In rare cases Likewise, statements that are no longer considered true in which one action occurred while another was should remain in the past tense: for instance, “bacteria ongoing, the past progressive is used (e.g., “while the were believed to lack introns” or “early physicists thought cells were incubating [past progressive], the temperature that electrons traveled in defined orbits.” At times, a was raised [past] 1°C per hour” or “while patients were combination of tenses is necessary: “Robert Corey preparing [past progressive] for surgery, nurses collected suggested [past] that DNA contained three helices, [past] baseline samples”). The past progressive is a but subsequent work has proved [present perfect] the combination of the verb ‘was’ or ‘were’ and the present existence of a double-helix structure.” participle (‘-ing’ form) of the verb. AJE is the leading provider of manuscript services to academics and researchers worldwide. AJE.com RESULTS. “our results demonstrate that magnesium is essential for Because the experiments described in the text were enzymatic function,” “Figure 1 shows our fluorescence completed before the paper was written, the results section data,” and “in this study, we report the discovery of a new of a manuscript is also largely written using the past tense species of frog.” Note that sometimes two tenses can be (for example, “we detected no fluorescence in the control found within the same sentence: “because no enzymatic sample” or “all participants reported a significant reduction activity was detected [past tense] in the absence of in pain”). In certain cases, however, the present tense is magnesium, our results indicate [present tense] that needed. As described above for the introduction section, magnesium is [present tense] absolutely required.” The the present tense is appropriate when referring to the present tense is appropriate for the last verb because entire paper or to individual elements of the manuscript the observation extends beyond the specific experiment (e.g., figures, tables, sections, results, or data). Examples referenced in the first part of the sentence; it is now of statements for which the present tense is best include considered a statement of fact based on the results. DISCUSSION. ABSTRACT. The discussion section follows the same rules as the The verb tense chosen for the abstract should be based previous sections of the manuscript. When referring to on the section of the text to which each sentence specific results or methods, use the past tense, but use corresponds. For example, introductory statements the present when presenting conclusions (“we conclude describing the current understanding of the issue should use that gene X is dispensable for ornithine synthesis”). the present tense, references to previous research should However, the discussion may include the future tense use the present perfect, and descriptions of the methods if directions for additional research or scholarship are and results should use the past tense. Indeed, one study of brought up (e.g., “the methods reported here will allow verb tense in English medical abstracts has revealed that the for rapid screening in the field” or “we will publish the full three most commonly used tenses are past, present, and results of our screen as part of another study”). present perfect6, in line with the conventions described here. In this paper, we have offered some advice for choosing verb tense in a scientific manuscript. Please note that these suggestions are not absolute rules, but following these guidelines will help your text conform to the conventions of scientific writing. Above all, it is important to be consistent with your choice of tense. If you have any questions about your writing, please contact us at [email protected]. Best of luck! 6 Salager-Meyer F “A text-type and move analysis study of verb tense and modality distribution in medical English abstracts.” Engl Spec Purp 11(2):93-113 (1992) AJE is the leading provider of manuscript services to academics and researchers worldwide. AJE.com ABOUT THE AUTHOR Dr. Mudrak is the Global Communications Manager at AJE, where he has worked since 2007. He graduated from Duke University with a PhD in Molecular Genetics and Microbiology and performed over eight years of research on pathogenic bacteria at Duke and the University of North Carolina at Chapel Hill. Prior to his current position, Dr. Mudrak led a number of webinars and workshops on academic writing and publishing as part of AJE’s Author Education program. AJE is the leading provider of manuscript services to academics and researchers worldwide. Manuscript Editing | Translation | Figures Services | Formatting OVER 200 FREE RESOURCES TO HELP YOU PUBLISH YOUR RESEARCH FASTER. VISIT OUR AUTHOR RESOURCE CENTER ARC.AJE.COM www.AJE.com 601 West Main Street, Suite 102, Durham, NC 27701 USA [email protected].